Greenhorn may refer to:
People Billy Greenhorn (1937–1995), American poet Stephen Greenhorn (born 1964), Scottish playwright and screenwriter
Places Greenhorn, California, United States Greenhorn Creek in Colorado, United States Greenhorn Mountain, a mountain in Colorado, United States The Greenhorn Valley in Colorado, United States Greenhorn, Oregon, United States
Other The Greenhornes, a rock band from Cincinnati, Ohio Greenhorn Limestone, a widespread geologic unit in the plains and mountainous Western United States